The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Electrochemical deposition (ECD), also called plating or electroplating, is used to deposit metals onto substrates. For example, ECD is used to deposit metals on interconnect structures in an IC package. Examples of the interconnect structures include bumps, pillars, through silicon vias (TSVs), and redistribution layers (RDLs). ECD is also used in multichip packaging and interconnection processes generally called wafer level packaging (WLP).